Run times and output of Malkoff LED drop-in's?

[cernobila]

I don't understand the differences in the following combinations as far as output and run times.......does anybody know this?

M60 with 2x CR123
M60 with 2x RCR123
M60 with 1x 17670
M60 with 1x 18650
AND
M30 with 1x 17670
M30 with 1x 18650

Thanks, any information on this would be very helpful.....I just want to know the most practical and efficient combination.

 

[etc]

I think M60 needs 2x18650 to even run, goes up to 9V.

 

[cernobila]

I think M60 needs 2x18650 to even run, goes up to 9V.

I know that some people use the M60 with 2x RCR123 cells but not sure if this is the best combination in a 6P size light, both thin and wide versions.

 

[LED_astray]

Just posted this link in another thread, plenty of run time measurements:

http://www.candlepowerforums.com/vb/showthread.php?t=194879

and other discussion, especially of running M60*'s on 18650's.


(Other thread:

http://www.candlepowerforums.com/vb/showthread.php?t=209210

might be interesting follow up there too.)

 

[etc]

I have the very same question. Some answers here:

http://candlepowerforums.com/vb/showthread.php?t=208214

Convert the modules power consumption to watts

convert the cells capacity to watt-hours

then you can figure it out.

The unknown variable I don't know, is whether gene tested his module at 750mA at 6V from a bench power supply, or from a pair of CR123s, this makes a slight difference in the results but I'm not going to get into that now...


Lets assume a constant 4.5W of consumption when the module is in regulation for comparison purposes.

this link:
http://www.candlepowerforums.com/vb/showthread.php?t=67078
shows some common discharge characteristics of CR123s, and we can make some estimates from this.

We know that a M60 draws ~750mA when you have 6V power supply, so if you had 3 CR123s in series, you would have more voltage, and less current draw (same 4.5W in the end). So the Performance of 3xCR123s driving an M60 should correlate to the 0.5A discharge chart semi-accurately. For comparisons sake, I'm going to go on the bet that you choose some good quality cells, and give the average CR123 a capacity value of 3.75 watt-hours per cell for this comparison.

This link:
http://www.candlepowerforums.com/vb/showthread.php?t=117117
shows some discharge characteristics of various size li-ion cells.

So lets assign some values to various size li-ion cells... now, keep in mind, most of these tests were performed at 1 amp or greater, this is a problem because we know that the malkoff M60, when powered by a ~7.4V source, will probably be drawing much less than 1 amp, probably closer to 600mA (guessing!). So we need to try to extrapolate some values that make sense. I'll do the pleasure:

1. 17500: 4.3 watt-hours
2. 18500: 5.1 watt-hours
3. 18650: 8.2 watt-hours

So now we need to add up the total available power in each configuration:

1. 3xCR123: 11.25 w/h
2. 2x17500: 8.6 w/h
3. 2x18500: 10.2 w/h
4. 18650 16.4w w/h

These are all educated guesses that will vary depending no many factors and what cells are chosen. but:
Based on these very rough numbers, I would say the comparison is as follows:

1. 3xCR123s: 2:30
2. 2x17500: 1:55
3. 2x18500: 2:16
4. 2x18650: 3:39

Eric

http://www.candlepowerforums.com/vb/showthread.php?t=208079

Not truly relevant to your question, but interesting anyway, output differences between various M60 modules. If you know the mAh consumption, you can compute runtime for them as well (M60L and M60LL)

http://www.candlepowerforums.com/vb/showthread.php?t=191547

 

[cernobila]

Thanks for all that, when I have time I will do the reading.....hope that the M30 is also mentioned in all that data I am about to read......

 

[etc]

This is all really good stuff, deserves to be consolidated in one thread:

Hey guys, I could not find any runtime info on the Malkoff M60 dropin using rechargeables so I ran some totally unscientific tests using 18650,17670, 18500 and RCR123's.
Of the M60, Gene states on his website: "The input voltage is 3.8 - 9 volts. Below 3.8 volts it will drop out of regulation and run direct drive. The runtime is 1 1/2+ hours on 2 CR123 primary batteries"
2 RCR123's seem to be the preferred choice but how about the single cell setup? Above 3.8 volts is the range where the light will run in regulation before we get decreasing light output. But how long do these single cells power the M60 in that regulated range? And is there any difference in brightness between the configurations? All cells used were hot off the charger reading 4.18-4.19 volts.

(2) AW 750 mah RCR123's in the Surefire C2 + M60 ran for 38 minutes before shutting off. In a second test with different RCR123's it ran for 41 minutes before shutting off.

(1) AW 1600 mah 17670 + SF C2 + M60 ran for 3 hours before I shut it off - it was very dim at that point. At the one hour mark I pulled the cell and measured the voltage - 3.78 volts. Roughly 1 hour of regulated output and 2 hours of declining output.

(1) AW 2200 mah 18650 + Leefbody + M60 ran for 3.5 hours before I shut it off (had to go to work) it was dim but not as dim as the 17670 test - probably would do 4 hours+. At the 1.5 hour mark I pulled the cell and measured the voltage - 3.83 volts. Over 1.5 hours of regulated output and 2 - 2.5 hours? of declining output.

It should be noted that although not noticeable (to my eyes) the RCR123 setup produces more output as measured by my cheap styrofoam cooler lightbox: 3730 lux verses 3300 lux using the18650.

A couple more tests:

(2) AW 1500 mah 18500 + Leefbody + M60 ran for 2 hours and 27 minutes before shutting off. There was no noticeable drop in output during the run.

(2) AW 2200 mah 18650 + Leefbody + M60 ran for 3 hours and 14 minutes before shutting off. Again no noticeable drop in output during the run.

The Malkoff M30 is not available on his website. If you want one you have to contact Gene and requested it. It looks identical to the M60 except for the engraving- rather than M60 you have: M30,1-4.5v. Ideal for a 3.7 volt single cell.

How does the M30 compare to the M60 when powered by a single 18650?

Lightbox:
M60 = 3300 lux
M30 = 4190 lux

Amp Draw:
M60 = .88 amps
M30 = 1.1 amps (after 2 minutes)

Runtime:
M60 = over 1.5 hours regulated / over 3.5 hours total
M30 = ran for 1 hour and 57 minutes before shutting off. No noticeable drop in output during the run. ( ran for 1 hour and 19 minutes on a 17670 before shutting off)

The M30 runs noticeably warmer (not hot) than the M60.
Cheers, Frank

 

[cernobila]

Well in that case why isnt the M30 more popular than it is? About two hours of regulated slightly brighter output than the M60.....that is pretty good in my book.....so why would you bother using the M60 in a 6p size light when the M30 would be a better choice (unless you want to use 2x CR123 cells and not rechargeables)

 

[Sgt. LED]

Because you actually have to take the time to E-mail him and ask him to make it for you.

People are weird like that, or lazy. Didn't slow me down any!

 

[cernobila]

OK, so another question......how would the M30 unit with its low level at about 1.5V go being run with only one CR123 cell, say in a 3P, or a 6P with a dummy cell? I know that 2x CR123 will fry it but one CR123 should be ok......wonder what the output/runtime would be with the M30/1x CR123 combination.......anyone have any idea?

 

[etc]

I couldn't put M30 in SF 9P.

 

[cernobila]

I couldn't put M30 in SF 9P.

What, physically? or because it would fry........

 

[Sgt. LED]

OK, so another question......how would the M30 unit with its low level at about 1.5V go being run with only one CR123 cell, say in a 3P, or a 6P with a dummy cell? I know that 2x CR123 will fry it but one CR123 should be ok......wonder what the output/runtime would be with the M30/1x CR123 combination.......anyone have any idea?

I know it will work just fine, but I am unsure on the runtime. 35/40 minutes?

Etc, it you want to try an M30 in your 9P buy 1 17650 and 1 123 size dummy cell and you are good to go. If it was me with your set-up I'd just be happy with what I have unless I needed a shorter light. Then I would save my money and just buy a 6P body from the marketplace.

 

[bagman]

I have a M30 on order that I plan to run in a 18650 Leaf body. I was getting it for the single cell rather than a pair of CR123A's (my set up at the moment) but it looks from this thread like it will be brighter as well

 

[cernobila]

OR use one CR123 and two dummy cells lol

.....or one RCR123 and two dummy cells......or.....?

 

[etc]

I don't, I am happy with the setup....

3x123 = 9V meaning it would fry M30 which is max at about 5V. There is a reason why M60 exists. In fact, even 2x123 should fry M30 (?)

 

[etc]

I have a M30 on order that I plan to run in a 18650 Leaf body. I was getting it for the single cell rather than a pair of CR123A's (my set up at the moment) but it looks from this thread like it will be brighter as well

.... but less runtime than 2x18650 body. Or 2x18500 or 2x17500 (I think) Or 3x123.

 

[cernobila]

.... but less runtime than 2x18650 body. Or 2x18500 or 2x17500 (I think) Or 3x123.

yes but smaller flashlight

 

[bagman]

.... but less runtime than 2x18650 body. Or 2x18500 or 2x17500 (I think) Or 3x123.

It will sit on my duty belt in a SF V70 holster so I am after the shorter light for this.

I do carry a 3 x 123 cell light on late shifts but that is now another Leaf body (2 x 18500) running a LF EO-9 Even brighter than my M60

 

[etc]

True enough ---